Developing a site classification system to assess the impact of climate change on species selection in Ireland.

Abstract

Correct matching of tree species to site is the first and most fundamental step in sustainable forest management. This key art, practised by foresters over centuries, was neglected in Britain and Ireland during a period of rapid forest expansion in the mid to late 20th century. The period of expansion was dominated by intensive site amelioration to plant a small number of chosen species. Forestry has matured to recognise sustainable management as key to the delivery of multiple values to society. Site classification can be used to re-establish the link between site type and species choice, and multifactor classification systems are currently used by forest practitioners in different countries. Since 2001, Ecological Site Classification (ESC) has provided support on ecological suitability analysis and site yield estimation for forest managers in Britain. Recently it has been extended to consider changes in suitability and yield resulting from different climate change scenario projections. We are now developing a similar system for site/species suitability analysis in Ireland in the CLIMADAPT project, which is part of the CLIM-IT programme funded by COFORD. CLIMADAPT will develop a decision support methodology, similar to ESC, using soil and climatic information for Ireland. The paper discusses the stand-based and spatial analysis modules within CLIMADAPT. Spatial information is useful for strategic decision making, and stand-based analysis is appropriate for operational decisions. CLIMADAPT will be delivered as a web-application, to allow wide access to practitioners in Ireland. Future climate projections suggest warmer, drier summers in the south and east of Ireland. This may affect growth and yield for drought sensitive species such as spruce, beech and ash. The project is also investigating the degree to which climate variables affect drought sensitive and drought tolerant species along a climatic gradient through Ireland and Britain. Knowledge and information about changes in species suitability, species tolerance and forest management adaptation will be incorporated within the decision support tool.